In his new book "Challenger: An American Tragedy - The Inside Story From Launch Control", Hugh Harris, the former "Voice of NASA" that counted down the launch that fateful day describes the scene in the control room

"As soon as it cleared the tower commentary changed to the Johnson Space Center and I was able to turn around, look out the window, and see what was happening," he recalls. "It was sort of unbelievable when we saw the flames start near the bottom and engulf the entire vehicle. It seemed like it took minutes for that to happen."